The present invention relates to a composition to be used for preservation of wood and wood-based materials, wherein said composition comprises 1-[[2-(2,4-dichlorophenyl)-1,3-dioxolan-2-yl]methyl]-1H-1,2,4-triazole, (b) at least one compound selected from the group consisting of o,o-diethyl o-(3,5,6-trichloro-2-pyridyl) thiophosphate, o,o-diethyl o-(.alpha.-cyano-benzylidene-amino) thiophosphate, o-ethyl o-(2,4-dichloro-phenyl)-S-n-propyl dithiophosphate and o,o-diethyl o-(1,6-dihydro-6-oxo-1-phenyl-3-pyridazinyl) thiophosphate and at least one diluent. Optionally, said composition further comprises at least one of the group consisting of another fungicide, a processing auxiliary, or additive, an organic chemical binding agent, a fixative, a dye, and a pigment. The present invention also relates to a process for preparation of the above-described composition for preservation of wood and wood-based materials.
The chemical compound, 1-[[2-(2,4-dichloro-phenyl)-1,3-dioxolan-2-yl]-methyl]-1H-1,2,4-triazole ("azaconazole"), having the structural formula ##STR1## is known, and has been described in German Patent No. 2,551,560 as a fungicidal and plant growth regulatory agent for agricultural use. It is not known, however, whether azaconazole can be used as a wood preservative.
Demands placed on a good wood preservative are considerably more than those placed on a fungicide used for plant protection. A fungicide need only be active against fungi, but a good wood preservative has to be active not only against wood-discoloring and wood-destroying fungi, but wood-damaging insects as well, particularly termites. Furthermore, a wood preservative, but not a fungicide, has to exhibit a good long-term activity.
Coincidentally, esters of thiophosphoric acid are known to exhibit good insecticidal action and have been employed in protection of plants against insects. But it is not known, however, whether these insecticides can also be used as wood preservatives. In general, a good insecticide for purposes of plant protection, by definition, is not a good wood preservative. This is because a good insecticide must be degraded after a certain period of time, thus eliminating the possibility of contamination of the food chain and endangering the health of humans and animals. Moreover, a good insecticide must not penetrate too deeply into parts of plants upon application, in order that it can be easily washed off. In contrast, long-term activity and good penetrating ability are necessary characteristics in preservatives for wood and wood-based material. For purposes of the present invention, a wood-based material is a material made from wood, such as plywood, pressed wood, particle-board and wood laminates.
It is also not known whether a combination of fungicide and insecticide can be used as a wood preservative, without one of them impairing the activity of the other. Even if these fungicides and insecticides, hereinafter collectively referred to as "biocides", can be used in combination as a wood preservative, it is not known what amount of each is necessary to produce an optimum product.